Previous research with children has documented age changes in communication accuracy. The proposed research examines the hypothesis that the ability to monitor one's own communication performance underlies the development of communication effectiveness. Self- monitoring ability is hypothesized to contribute to the speaker's capacity to benefit from feedback about his communications. The proposed research will provide procedures for assessing self-monitoring skill, examine the development of self-monitoring and experimentally examine the relationship between self-monitoring and the utilization of communication feedback. To assess self-monitoring children and adults will be asked to predict the impact of their own versus someone else's communications. Video playback will serve as feedback of speaker communication. Pre- and post-feedback communication will provide the basis for measuring the impact of feedback.